Carbureter and combined carbureter and regulator



March 12, 1963 R. F. ENSIGN CARBURETER AND COMBINED CARBURETER ANDREGULATOR Filed Dec. 15, 1958 4 SheetsSheet l Mad.

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March 12, 1963 R. F. ENSIGN 3,081,160

CARBURETER AND COMBINED CARBURETER AND REGULATOR Filed Dec. 15, 1958 4Shee tsSheet 5 IN VEN TOR.

March 12, 1963 R. F. ENSIGN 3,081,160

CARBURETER AND COMBINED CARBURETER AND REGULATOR Filed Dec. 15, 1958 4Sheets-Sheet 4 :96 46? 502 422 a "Q 3C Bay JW E A/s/G INVENTOR.

Unite Stae 3,081,160 CARBURETER AND CGMBINED CARBURETER AND REGULATQRRoy F. Ensign, Fullerton, Califl, assignor, by mesne assignments, toAmerican Bosch Arrna Corporation, a

corporation of New York Filed Dec. 15, 1958, Ser. No. 738,512 1 (Ilaim.(Cl. 48-484) This invention relates to carbureters andcarbureterregulator combinations for forming and feeding gaseous fueland air mixtures to devices using such mixtures, for example internalcombustion engines. The carburetors and carburetor-regulatorcombinations of the invention have been designed with a particular viewto being installed on the upper air intakes of down-draft liquid fuelcarburetors, where the vertical space between those intakes and thecovering hood in an average automobile is restricted. That is one of theobjects and advantages of the invention; but, as will appear from thefollowing descriptions, there are other accomplishments and advantagesof the invention that are not dependent on that use. Accordingly theinvention is not limited to that specific use. The objects andcorresponding accomplishments of the invention will be best understoodfrom the following descriptions of structures in the nature ofillustrative embodiments of the invention, and their modes of operation.Such illustrative embodiments are shown in the accompanying drawings,where:

FIG. 1 is a central sectional view of one form of combined carburetorand regulator, with certain parts in elevaticn;

FIG. 1a is a fragmentary sect-iton of those certain parts of FIG. 1;

FIG. 2 is a section on line 22 of FIG. 1;

FIG. 3 is a central section of a carburetor of the type shown in FIG. 1;and

FIGS. 4, 5, 6 and 7 are central sections of modified forms of thecarburetor of the invention.

Referring first to the form of carbureter shown in FIGS. 1, 2 and 3, abase member 20 is formed with an outlet passage 22 adapted at 24 to besecured to and communicate either with the intake manifold of an englue,or of any other device using the produced combustible mixture, or withthe air intake of a liquid fuel carburetor, such for instance as isshown at 26 in FIG. 4-. "FIGS. 1 and 3 show the outlet passage 22equipped with a throttle 28; but if any of the carburetors heredescribed are mounted on the air intake of a liquid fuel carbureter, thethrottle normally associated with the air and mixture passage of thatcarburetor will, or can, control the output of the carbureters heredescribed.

Member 20 forms the base wall or plate of an air intake chamber 62 whoseside wall, preferably circular, is formed by an annular air filter 36,here shown as made up of two spaced screen Walls 32 with a suitablefilter filling 34 between them. A cover plate 36, held down by suitablemeans such as screws 38, forms the top wall of the chamber.

Referring for the moment more particularly to FIG. 3, a gas distributionchamber 40 of fiat circular shape, is formed within top and bottom wallmembers 42 and 44, held together and held down on spacers 46 by screws48 which are spaced around members 42, 44 as shown in FIG. 2. As willappear, the section of FIG. 2 applies to the form of FIG. 3 as well asthat of FIG. 1, excepting only certain details of difference. Spacers 46space bottom wall member, and the whole gas distribution chamber 40,above base wall 20. In the form of FIG. 3, the feed of gaseous fuel atsuitable pressure to the disassess: Patented Mar. 12, 1953 2 tributionchamber 40 is via a short nipple 50 forming an extension of the initialinlet fitting 52 secured to the under side of 20. The vertical spacingof 44 above 20 may be adjusted by substituting spacers 46 of differentlengths; and nipple 50 may have a close sliding fit in opening 54 tofacilitate that adjustment.

Bottom wall 44 of the gas distribution chamber 40 has a plurality of gasoutlet orifices 56 in circular arrangement concentric with the axis ofchamber 40. As shown in FIG. 2, there are, for example twelve of theorifices 56. These orifices discharge directly into the space 60 betweenthe distribution chamber 40 and the base wall 20. The passage formed bythat space constitutes the venturi of the carbu-reter, as will appear.In this connection note that the circular array of evenly spacedorifices 56 is outside the maximum circular size of outlet 22, withwhich the orifice array is in concentric relation. The maximum circularopening of outlet 22 is indicated at 22a, in FIGS. 1, 2 and 3.

Assume a suction (eg, the suction of an internal combustion engine)applied to outlet 22. Air will be drawn in through filter 30 uniformlyaround its circular extent, and drawn under chamber '40 in circularuniformity radially inwardly to the outlet. In flowing through thepassage formed by the spacing 60 the air flow has a velocity dependenton its volumetric flow and the vertical width of that passage. Thatvelocity causes a lowering of pressure by venturi action in the passage60, and that lowered pressure draws the fuel gas through orifices 56 tomix with the air flow going out through 22. The feed of gas to 40 via 52will preferably be at about atmospheric pressure, or, under pressureregulator controls Well known in the art, at about the effectivepressure in the air intake chamber 62 surrounding gas distributionchamber 40. In FIG. 1, where a pressure regulator is combined with thecarbureter, the gas feed pressure is automatically regulated to bear afixed relation to the effective pressure in the air chamber.

The carbureter shown in FIG. 1 is essentially the same as that shown inFIG. 3, except for the position of the initial gas feed opening to thegas distribution chamber, and the location of the screws 38 that holdcover 3'6 down. Parts that are the same as in FIG. 3 are given the samenumerals.

In FIG. 1 the upper wall member 420 of distribution chamber 40 isextended to form the lower half of a regulator chamber enclosure, with asurrounding wall 42b. That chamber 7!), closed at its top by diaphragm72, is the delivery chamber of the regulator in which the pressure isregulated by the action of the diaphragm on inlet valve 74- throughvalve lever 76. The upper side of the diaphragm is directly exposed tothe existent pressure in air chamber 62, but preferably covered byprotective cover '78 having an aperture 81} through which the diaphragmis directly and freely exposed to the pressure in the surroundingchamber 62. Valve 7-4 controls an inlet 82 which is fed with gas undersuitable pressure through a nipple 84 leading from inlet fitting 86.Nippic 84 may have close sliding fit at either its upper or lower end tofacilitate adjustment in the width of passage space 60 as beforeexplained. Delivery chamber 79 delivers directly to distribution chamber46 through an opening 54a which may be quite large; in full effectchamber may normally be preferably wide open to chamber 469 if aneconomizer (see below) is not used.

If the valve-diaphragm system 72, 74 is not biased in either direction,the pressure at which the regulator delivers, and the pressure inchambers 44) and 70, will be the same as the effective air pressure inair intake chamber 62. Preferably, however, the system is slightlybiased by spring in valve closing direction so that the valve will closewhen pressures on opposite faces of the diaphram are equal.

Whether or not the system is biased, the delivery pressure in 70 and 40always bears a fixed and definite relation to that in air intake chamber62. Chamber 62 forms the air intake to the carbureter. In the usualarrangement for feeding gaseous fuel from a pressure regulator to theusual carburetor, a balance tube, sometimes quite long, extends from theair intake to the regulator reference chamber at the outer face of thecontrolling diaphrag-ma chamber like that here shown at 78a under cover78. On rapid changes of efiective pressure in the air intake, the lengthof the balance tube slows down the delivery pressure response of theregulator to such pressure change. But here, with the regulator locatedin the air intake, control diaphragm 72 is directly and immediatelyexposed to the air intake pressure. Cover 78 may be omitted; but in anycase opening 80 is large enough that the diaphragm is directly andfreely exposed to the pressure in 62.

Another advantage inherent in the combination of FIG. 1 is the directand open communication of regulator chamber 70 with distribution chamber40. In full effect the two chambers are one, except that it may bepreferable to feed 40 through a central opening 54a sym metric withrelation to the circular array of orifices 56, or at least not oppositeany of them.

This wide open communication makes it practicable to control theair-to-fuel ratio solely by the sizing of orifices 56. The same may besaid of FIG. 3, providing the feed tube 52 from the pressure regulatoris made large enough. Ordinarily however such feed tubes are long, and amixture controlling adjustment valve is incorporated in them.

The combination arrangement of FIG. 1 also makes it possible toincorporate certain mixture ratio controlling devices in a very simpleand direct manner. For example, an economizer 100 is shown in FIG. 1 andin enlarged sectional detail in FIG. la. As there shown a smalldiaphragm 102 has a diaphragm chamber 104 above it closed by cover 106.Chamber 104 is subjected to engine intake suction from beyond throttle28 via pasmges 108 and slip nipple 110. The diaphragm carries a valveclosure 112 which, on upward diaphragm movement, closes down the port114 that, like port 5411, leads directly through wall 42a from chamber70 to distribution chamber 40. The bottom wall 107 of the economizerbody is spaced above wall 42a by spacers 109, so that port 114 is infree communication with chamber 70. A spring 116 biases the diaphragmand valve down to keep port 114 open when the manifold depression islow, as it is at wide open throttle and engine operation at full power.At medium ranges of operation, with greater manifold depression, valve112 is moved upwardly to close port 114 down. With port 114 open,chamber 70 may be wide open to 40. With port 114 closed down thecommunication of 70 to 40 is correspondingly reduced, to thin thefuel-and-air mixture for economy. The range of economizer action can beadjusted by changing the removable valve seat 115 that carries port 114to substitute ports of different sizes. Port 54a may likewise be formedin a removable member 55 so that the siZe ratio of ports 54a and 114 maybe adjusted. Although port 114 may be large enough, with valve 112 open,to constitute the whole free feed from 70 to 40, preferably the majorfeed is through 54a. and the relative eiiective size of 114 iscomparatively small.

FIG. 4 shows a variant carbureter form in which the gas distributionchamber, located in the air intake chamber 62, is associated with thetop cover plate and the gas feed is into the distribution chambercentrally from above.

As shown here the base wall 201 has an upstanding walled deliverypassage 221. The base wall 201, filter 30 and cover plate 361 enclosethe air intake chamber 62 around 221 and the distribution chamber 401.Cover 361 forms the upper wall 421 of the distribution chamber. Itslower wall 44 is provided with the described circular array of orifices56. Gas feed is through the central port 541 through wall 421. Spacedbelow wall 44 by spacers 461 to form the venturi passage 601 is a plate201a with a discharge neck 221a having a close sliding fit in delivery221. This fit facilitates adjustment of the width of the venturi passage601 by changing spacers 461; the parts 201a, spacers 461, and wall 44all being held to cover 361 by the screws 481.

The carbureter operation here is in substance the same as in FIGS. 1 to3. Air fiows radially inwardly in circular uniformity from air chamber62 through the venturi passage 601 to reach the central discharge neck221a, drawing the gas through orifices -56. Discharge neck 221a has thesame concentric relation to the circular array of orifices 56 asdescribed for outlet 22 in FIGS. 1 to 3. The regulator of FIG. 1 can bemounted on the upper wall 421 of the gas distribution chamber here, thesame as it is mounted on corresponding upper wall 42a in FIG. 1; withthe same direct connection between the regulator delivery chamber andthe distribution chamber.

In the form shown in FIG. 5, the venturi passage 602 is formed betweenthe distribution chamber 402 and the cover plate 36. Base 202 carries anupstanding walled outlet 222 and the lower Wall member 442 of thedistribution chamber rests on the wall of that outlet. Upper wall 422has the described circular array of gas discharge apertures 56concentrically surrounding the central discharge passage 224 thatextends through the annular distribution chamber 402. The distributionchamber is spaced below the cover plate by spacers 462. The wholeassembly is held together by the bolt 382 that holds cover 36 down onthe annular filter 30. The initial gas feed is similar to that in FIG.3, through a nipple 502 from inlet fitting 52. Adjustment of the widthof venturi passage 602 may be made by substituting spacers 462 andeither changing the height of outlet wall 222 or by placing an annularspacer under cover 36' on top of filter 30.

Air from air intake chamber 62 flows radially inwardly in even circulardistribution through venturi passage 602 and over the gas orifices 56,and thence the mixture flows down throught central outlet passage 224and discharge 222.

The form of B66 is generally similar to that of FIG. 5, but the venturipassage 605 is here formed between a plate 36-5 and the upper orificedwall of the distribution chamber. In this form the lower base member 205has a central upstanding walled discharge 225. The distribution chamber405 is formed around the discharge wall Within and below an annular wall425 that rests on base 205. The upper part of annular Wall 425 isconvexly curved in section, as seen at 425a in the figure, and thecircular array of orifices 56 is placed at the top of the convex curve.Plate 365 is adjustably spaced above the orificed wall by spacers 465,and the venturi passage at 605 is formed between that plate and theconvex orificed wall. Initial gas feed is from inlet fitting 52, whichis here shown fitted with a flow adjustment plug 525. Operation is thesame as in FIG. 5.

In all of the forms so far described the air flow through the venturipassage is radial and circularly evenly distributed. That is also trueof the form of FIG. 7 which is similar to FIGS. 4 and 6 but not, asshown, including a surrounding air filter and air intake chamber.

In FIG. 7, the annular gas distribution chamber 406 is enclosed in upperand lower annular walls 426 and 446 which form the central air inletopening 62a into which air may flow directly from atmosphere, or throughan inlet fitting such as 62b which may be equipped with a filter. Or,instead of using the air inlet fitting 62b, the carbureter structure ofthis figure may be enclosed within the surrounding air chamber, as, forinstance, in FIG. 5. Lower wall 446 of the distribution chamber restsdirectly on the walled discharge member 226. described circular array ofgas outlet orifices 56 is in lower Wall 44 6 surrounding the central airinlet 62a. A circular venturi forming plate 366 is adjustably spacedbelow lower Wall 446 by spacers 466, its periphery being spaced inwardlyfrom the wall of 226 to allow an annular discharge passage. Initial gasfeed is by fitting such as 52 connected directly to the distributionchamber.

In operation air is drawn down through central air inlet 62a and thenflows radially outwardly in even circular distribution through theventuri passage 666 over plate 3566 and under gas orifices 56. Themixture then flows outwardly and down over the periphery of 366 and downthrough discharge 226.

A characteristic of all of the several forms resides in the radial andcircularly distributed air flow through a venturi passage where onepassage forming wall has a circular array of gas orifices discharginggas into the radial air flow at a number of distributed points. One ofthe beneficial results of this arrangement is a marked improvement ineven distribution and admixture of the gas to form a final mixturehaving the same mixture ratio in all its parts.

Another advantage inherent in the designs of the invention is therelatively short axial length of the whole carburetor assembly, thewhole assembly being flat rather than long. And the assembly lendsitself most readily to being completely enclosed Within an annular airfilter. And within the air inlet chamber within the filter a pressureregulator can be mounted in direct feed communication with the gasdistribution chamber, and in direct pressure control exposure to theeffective air pressure in the air inlet chamber.

I claim:

A combined carbureter and pressure regulator, comprising in combinationa substantially flat, circular, walled air inlet chamber enclosed by twosubstantially circular spaced walls 40 2,939,775

The

and a peripheral air filtering wall, a discharge outlet leading throughone of said walls,

wall structure forming a circular gas distribution chamber within theair inlet chamber,

the distribution chamber having a circular wall fixedly spaced from saidone wall of the air inlet chamber, in concentric relation to, andextending radially outward beyond, the discharge outlet,

the space between the two spaced walls being open at its outer peripheryto the interior of the air inlet chamber and forming a passage throughwhich air may flow radially inwardly to said outlet,

a circular array of spaced gas distribution orifices extending throughsaid circular distribution chamber wall in concentric relation to saiddischarge outlet and radially outward therefrom,

a gas ressure regulator mounted directly on a wall of the distributionchamber opposite its said orificed wall and located entirely within theair inlet chamber,

said pressure regulator having a delivery chamber in open communicationwith said distribution chamber,

a pressure regulating diaphragm forming a wall of the delivery chamberopposite the distribution chamber and exposed on its inner facecompletely and solely to gas pressure in the delivery and distributionchambers,

the outer face of said diaphragm being exposed directly, completely andsolely to the air pressure in said air inlet chamber,

a fuel gas inlet to said delivery chamber,

and diaphragm actuated valve means controlling said gas inlet.

References Cited in the tile of this patent UNITED STATES PATENTS1,292,677 Barrett Jan. 28, 1919 2,754,185 Ensign July 10, 1956 2,871,976Sebok Feb. 3, 1959 2,927,848 Baverstoek Mar. 8, 1960 Middleton June 7,1960

